This research project has two objectives. The first is aimed at understanding the normal postnatal development of the dorsal lateral geniculate nucleus of the cat. Light and electron microscopic methods are being employed to investigate the maturation of lateral geniculate cells and the synpatic relations which they form. The second objective is to assess the influence of both partial and complete visual deprivation on the normal sequence of lateral geniculate development; and, in particular, to determine if there exists a specific developmental period during which the lateral geniculate is especially sensitive to the effects of deprivation. BIBLIOGRAPHIC REFERENCE: Moore, C.L., Kalil, R.E., and Richards, W. 1976. Development of myelination in optic tract of the cat. J. Comp. Neur., 165, 125-136.